XmlEscapeDirective.java

/* Copyright (2012) Schibsted ASA
 * This file is part of Possom.
 *
 *   Possom is free software: you can redistribute it and/or modify
 *   it under the terms of the GNU Lesser General Public License as published by
 *   the Free Software Foundation, either version 3 of the License, or
 *   (at your option) any later version.
 *
 *   Possom is distributed in the hope that it will be useful,
 *   but WITHOUT ANY WARRANTY; without even the implied warranty of
 *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *   GNU Lesser General Public License for more details.
 *
 *   You should have received a copy of the GNU Lesser General Public License
 *   along with Possom.  If not, see <http://www.gnu.org/licenses/>.
 *
 * XmlEscapeDirective.java
 *
 * Created on April 28, 2006, 2:49 PM
 *
 */

package no.sesat.search.view.velocity;

import java.io.IOException;
import java.io.Writer;

import org.apache.commons.lang.StringEscapeUtils;
import org.apache.velocity.context.InternalContextAdapter;
import org.apache.velocity.exception.MethodInvocationException;
import org.apache.velocity.exception.ParseErrorException;
import org.apache.velocity.exception.ResourceNotFoundException;
import org.apache.velocity.runtime.directive.Directive;
import org.apache.velocity.runtime.parser.Token;
import org.apache.velocity.runtime.parser.node.Node;

/**
 *
 *
 * @version $Id$
 */
public class XmlEscapeDirective extends Directive {

    private static final String NAME = "xmlescape";

    /**
     * {@inheritDoc}
     */
    public int getType() {
        return LINE;
    }

    /**
     * {@inheritDoc}
     */
    public String getName() {
        return NAME;
    }

    /**
     * {@inheritDoc}
     */
    public boolean render(final InternalContextAdapter context, final Writer writer, final Node node) throws IOException, ResourceNotFoundException, ParseErrorException, MethodInvocationException {
        if (node.jjtGetNumChildren() != 1) {
            rsvc.error("#" + getName() + " - wrong number of arguments");
            return false;
        }

        if (node.jjtGetChild(0).value(context) != null) {

            final String input = node.jjtGetChild(0).value(context).toString();

            if (input != null) {
                writer.write(StringEscapeUtils.escapeXml(input));
            }

            final Token lastToken = node.getLastToken();

            if (lastToken.image.endsWith("\n")) {
                writer.write("\n");
            }

        }
        return true;
    }
}